1. Field of the Invention
This invention relates to improvements in a side door hinge mechanism in a motor vehicle through the utilization of a quadric rotary link mechanism.
2. Description of the Related Art
In most cases, the side door in a motor vehicle, e.g. passenger can has heretofore been installed in a manner to be rotatable about a hinge affixed to a vehicle body for opening or closing. In order to allow an occupant of the motor vehicle to open or close the side door for getting in and out of the motor vehicle, a door opening angle commensurate to the total length of the side door is required. At this time, when a space outwardly of the motor vehicle is small, there are many cases where it is difficult for the occupant to get in and out the vehicle because the side door cannot be opened sufficiently.
In contrast thereto, as disclosed in Japanese Utility Model Laid-Open (Kokai) Nos. 46014/1982 or 101263/1980 for example, there has been proposed a side door hinge mechanism through the utilization of a quadric rotary link mechanism, wherein the quadric rotary link mechanism comprises: a rotary link interconnecting a point on a body of vehicle and another point on a side door as rotary centers out of two points spaced apart from each other on the body and two points spaced apart from each other on the side door; another rotary link interconnecting the other point on the body and the other point on the side door as being centers; a portion between the two rotary centers on the body; and another portion between the two rotary centers on the side door.
The side door hinge mechanism utilizing the above-described quadric rotary link mechanism makes it possible for the occupant to reduce the necessary space outwardly of the motor vehicle while securing a space at his feet. In consequence, even when the space outwardly of the motor vehicle is small, the occupant can get in and out of the motor vehicle by opening or closing the side door.
Now, for the side door in a motor vehicle, there has been provided a door check mechanism wherein the feeling of click action is formed by the opening degree of the side door, the side door is prevented from opening more than a predetermined extent, and the opening-closing speed of the door is regulated.
In general, this door check mechanism is of such an arrangement that a check arm is supported on a pillar portion on the side of the vehicle body, and a door check body being in sliding contact with this check arm to form a checking force is housed in the main body of the side door.
However, in the side door hinge mechanism in a motor vehicle, utilizing the above-described quadric rotary link devices, the opening-closing locus of the side door is not a simple circularly arcuate locus, so that the check mechanism cannot be mounted between the door and the pillar as seen in the conventional side door.
As against the above, in Japanese Utility Model Application No. 123046/1983, the applicant of the present invention has proposed a side door hinge mechanism in a motor vehicle, wherein, even with the side door hinge mechanism utilizing the quadric rotary link devices, the door check mechanism can be secured thereto.
Here, the door check mechanism proposed in Japanese Utility Model Laid Open Application No. 31,474/1985 is constructed such that the check arm is slidably extended through the door check body.
Now, when the side door hinge mechanism in a motor vehicle, utilizing the quadric rotary link devices as described above is disposed between the end panel at the forward end of the side door and the side surface of the vehicle body as proposed in Japanese Utility Model Laid Open Application No. 64,122/1985 for example, the side door hinge is provided at a position into which water, sand, mud and the like comparatively easily intrude as compared with the conventional cases.
If the above-described door check mechanism is mounted to the side door hinge mechanism provided at the aforesaid position, then such disadvantages are presented that sand, mud and the like adhere between a check arm an a check body, whereby a force necessary for the operation during opening or closing of the side door is increased and troubles tend to occur.
Since the aforesaid door check mechanism has heretofore caused operation failures when the coating material adheres thereto and has not been able to bear the highly heated atmosphere in the coating drying furnace, the check mechanism has had to be assembled after the motor vehicle is coated, i.e. assembled separately of the assembling of the side door hinge mechanism, thus presenting the disadvantage of lowering the assembling efficiency.
Since the check body and the check arm, which constitute the check mechanism, are mounted to the members separate of each other, an inclination, a twist and the like may be caused between the check arm and the check body depending upon the dimensional accuracy and the assembling accuracy of these members.